A methane problem in Utah

An oil rig operates in the Book Cliffs area, which is in the Uintah Basin. A federally backed study has found that 9 percent of methane produced from drilling sites in a portion of Utah's Uintah Basin escaped into the atmosphere.

Almost a tenth of the methane produced from oil and gas operations in a Utah site escapes into the atmosphere, according to a federally backed study published Monday.

It found that 9 percent of methane produced from drilling sites in a portion of Utah's Uintah Basin escaped, said Colm Sweeney, one of the study's main authors and a scientist at the National Oceanic and Atmospheric Administration's Earth Systems Research Laboratory in Boulder, Colo.

Brian Straessle, a spokesman for the American Petroleum Institute, said the industry trade association hasn't reviewed the new report, but cited other studies that found the portion of methane that escapes from wells is less than 2 percent.

Sweeney said the higher level found in the Uintah Basin study could cancel out environmental advantages of burning natural gas produced there.

He noted that natural gas is efficient because compared with other fossil fuels its combustion releases less of the greenhouse gas carbon dioxide, which is linked to climate change.

“But in order to properly account for this global warming benefit, you have to account for the leakage from the well hole to the point of use — and so that's the critical problem that we're trying to understand better,” Sweeney said.

High emissions of methane are troubling, Sweeney said.

“Methane immediately out of the ground will have a warming potential that is 100 times greater than carbon dioxide,” he said. “So you need a lot less methane to get a much higher global warming effect.”

Oil and gas companies have the means to cut down emissions to ensure that natural gas provides its full benefit as a low-carbon-emitting alternative to other fossil fuels, said Mark Brownstein, chief counsel for the Environmental Defense Fund's U.S. climate and energy program.

“Understanding that there are leaks is not to say that they can't be fixed,” Brownstein said. “But you can't solve a problem if you're unwilling to at least understand the magnitude of the problem and the sources of the problem.”

To better gauge the issue of methane leaks from oil and gas operations, nine energy companies have partnered with the Environmental Defense Fund and the University of Texas to determine the extent of leaks and their sources.

Straessle, the industry group spokesman, said producers “have every incentive to capture emissions so they can sell more of the natural gas they extract instead of losing some to the atmosphere.”

“The industry has led efforts to reduce emissions of methane by developing new technologies and equipment, and these efforts are paying off,” he said.

Such efforts can include “green completions” of wells, which capture and separate natural gas that flows along with water and mud out of a newly drilled well, Brownstein said. The process is key because it feeds the gas into gathering systems or readies it to be burned off in cases where it can't be moved into pipelines, Brownstein said.

In the Uintah study, researchers used 11 aircraft flights to measure methane emitted into the atmosphere above the basin. One flight produced especially clear results because it was conducted after high winds had blown away lingering pollutants, allowing researchers to capture methane leak data that was limited to energy company operations on that day, Sweeney said.

“The methane that we were measuring downwind was coming from a very recent emission,” he said.

The researchers estimated the amount of methane being produced in a 1,000-square-mile survey area, and arrived at the 9 percent calculation by applying their atmospheric methane readings to the total production, Sweeney said.